Well, Anno probably had not too much to do with it, since it lacks in microtransactions. But that is exactly what drove the sales apparently: "Higher-than-expected performance,led notably by Assassin’s Creed®Odyssey,Rainbow Six®Siege, and Player Recurring Investment". Especially Rainbow Six Siege is notable, as it has now the highest player it ever had, 4 years after launch.
Also, while it's 34% to 31%, keep in mind that last year it was 24% to 38%, so PC is 10 points higher while the PS4 dropped by 7 points, which are pretty substantial movements. And Switch is stuck at just 5%
They specifically state Anno is the reason.
" They attributed the PC surge primarily to the strength of the strategy game Anno 1800.
"The 34 percent was pushed by Anno, which is a PC-specific game, but even with that launch, we had a very good performance on PC overall," Ubisoft CEO Yves Guillemot said during an investors call."
LTD: PS4 - 125m, Switch - 110m, XBO - 51m
2020: PS4 - 9m, Switch - 22.5m, XBO - 2.5m, PS5 - 4.5m, XBX - 2.8m